Amino Acids, Aromatic Compounds, and Carboxylic Acids: How Did

Jan 1, 2000 - This article provides a brief survey of the origins of the common names of some amino acids, aromatic compounds, and ... Keywords (Domai...
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In the Classroom

Amino Acids, Aromatic Compounds, and Carboxylic Acids: How Did They Get Their Common Names? Sam H. Leung Department of Chemistry, Washburn University, Topeka, KS 66621; [email protected]

Organic chemistry students spend a considerable amount of time learning how to name organic compounds systematically, but they still encounter compounds whose common names are used very often or exclusively. Since the origins of these names are related to the sources, colors, or other unique characteristics of the compounds, it would be interesting to let the students know how some of these names came into existence. Although some textbooks occasionally mention the roots of these names, most of them do not devote a lot of space for this purpose. Common names are often more interesting than systematic names. Therefore, the derivations of the common names may make learning about the compounds more enjoyable. Articles concerning the origins of the names of the chemical elements have been published in this Journal (1, 2). However, a compilation of the name origins of common organic compounds has not appeared. This article provides a survey of the roots of the common names for organic compounds that are most likely to be encountered by undergraduate organic chemistry students. It is not intended to give an in-depth account of the origins but rather a brief look at the roots of the common names. The information, although brief, will allow the students to learn how these compounds got their names. The listings are best used as items of interest and will help lighten up the subject of organic chemistry. The compounds chosen are divided into three general groups: amino acids (Table 1), aromatic compounds (Table 2),

and carboxylic acids (Table 3). Roots of the names and additional notes are given to explain the origin of the common names. Systematic names are included for comparison with the common names and to facilitate structure identification. Acknowledgments I would like to thank the reviewers and the Editor of this Journal for their valuable suggestions. Literature Cited 1. Ringnes, V. J. Chem. Educ. 1989, 66, 731. 2. Ball, D. W. J. Chem. Educ. 1985, 62, 787. 3. Nickon, A.; Silversmith, E. F. Organic Chemistry: The Name Game; Pergamon: New York, 1987. 4. Bruice, P. Y. Organic Chemistry, 2nd ed.; Prentice Hall: Upper Saddle River, NJ, 1998. 5. The Oxford English Dictionary, 2nd ed.; Simpson, J. A.; Weiner, E. S. C., Eds.; Clarendon: Oxford, 1989. 6. Webster’s New International Dictionary of the English Language, 2nd ed., Unabridged; Neilson, W. A., Ed.; Merriam: Springfield, MA, 1950. 7. Noller, C. R. Chemistry of Organic Compounds, 2nd ed.; Saunders: Philadelphia, 1957. 8. Vollhardt, K. P. C.; Schore, N. E. Organic Chemistry, 2nd ed.; Freeman: New York, 1994. 9. Brown, W. H.; Foote, C. S. Organic Chemistry, 2nd ed.; Saunders: Fort Worth, TX, 1998.

Table1. Amino Acids Common Name a

Root b

Notes

Systematic Name

Ref

Arginine

L argentum, silver

forms a well-defined silver salt

(S)-2-amino-5-guanidinopentanoic acid

3

Asparagine

asparagus

first found in asparagus

(S)-2-amino-3-carbamoylpropanoic acid

4, 5

Aspartic acid —

related to asparagine

(S)-2-aminobutanedioic acid

5

Cysteine

reduction product of cystine (which see)

(S)-2-amino-3-mercaptopropanoic acid

5



Cystine

Gk kystis, bladder

first isolated from a bladder stone

bis(2-amino-2-carboxyethyl)disulfide

Glutamic acid

gluten + amino

obtained by the hydrolysis of gluten, a protein-rich product obtained in the separation of starch from corn or wheat

(S)-2-aminopentanedioic acid

3 3, 6

Glutamine



derived from glutamic acid (which see)

(S)-2-amino-4-carbamoylbutanoic acid

Glycine

Gk glykys, sweet

tastes sweet

aminoethanoic acid

6

Histidine

Gk histion, tissue



(S)-2-amino-3-(5-imidazolyl)propanoic acid

6

Isoleucine



isomer of leucine (which see)

(2S, 3S)-2-amino-3-methylpentanoic acid

5

3, 4

Leucine

Gk leukos, white

obtained in the form of white plates

(S)-2-amino-4-methylpentanoic acid

3

Lysine

Gk lysis, loosening

discovered among the products from the hydrolysis of casein

(S)-2,6-diaminohexanoic acid

3

Methionine

methyl + thio

contains a S atom (Gk theion, sulfur) with a methyl group attached

(S)-2-amino-4-methylthiobutanoic acid

6

Proline

pyrrolidine

contains a pyrrolidine ring

2-pyrrolidinecarboxylic acid

3 5

Serine

L sericum, silk

first isolated from silk

(S)-2-amino-3-hydroxypropanoic acid

Threonine

threose

spatial configuration analogous to that of D-threose, a 4-carbon sugar

(2S,3R)-2-amino-3-hydroxybutanoic acid

5

Tryptophan

tryptic + phane

obtained from the pancreatic (tryptic) digestion of proteins: tryptic, the adjective form of trypsin, a pancreatic digestive enzyme; phane, from Gk phanein, to appear

(S)-2-amino-3-(3-indolyl)propanoic acid

5

Tyrosine

Gk tyros, cheese

found in cheese

(S)-2-amino-3-(4-hydroxyphenyl)propanoic acid 3, 4

Valine

valeric

carbon skeleton corresponds to isovaleric acid (3-methylbutanoic acid)

(S)-2-amino-3-methylbutanoic acid

4

biologically important α-amino acids are almost always called by their common names. The suffix -ine is a common ending for compounds containing nitrogen (amine bases). b L indicates Latin; Gk indicates Greek. a These

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Journal of Chemical Education • Vol. 77 No. 1 January 2000 • JChemEd.chem.wisc.edu

In the Classroom Table 2. Aromatic Compounds Common Name

Root a

Notes

Systematic Name

Ref

Aniline

Sp añil, indigo; anil + -ine

first obtained by distillation of indigo; anil is the name for the West Indian shrub Indigofera suffrutincosa, one of the plants that produce indigo

aminobenzene

3, 7

Anisole

Gk anison, anise L ole, oil

anise is the name of the Egyptian plant Pimpinella anisum, which produces aniseed

methoxybenzene

6

Anthracene

Gk anthrax, coal

a constituent of coal tar

anthracene

Catechol

catechu + -ol

from gum catechu, an astringent substance obtained from various tropical plants

1,2-dihydroxybenzene

7

Cresol (o-, m-, p-)

prob. G kresol

from creosote, an oily liquid with a burning, smoky taste, obtained by the distillation of wood tar

1-hydroxy-x-methylbenzene b

6

from cumin, a plant native to Egypt and Syria

isopropylbenzene

5, 6

L furfur, bran

short for "furfurane"; obtained by decarbonylation of furfural, which was produced by distillation of bran with dilute sulfuric acid

furan

3, 7

produced by reduction of quinone; first obtained by oxidation of quinic acid

1,4-dihydroxybenzene

3, 7

indigo

first obtained by distilling oxindole, a degradation product of indgo, with zinc dust

indole

7

from mesite (Gk mesos, between), a liquid whose properties were once thought to be between alcohol and ether and later found to be acetone; mesitylene was so named because it can be made by condensation of three molecules of mesite

1,3,5-trimethylbenzene

3

phene, an old name for benzene; first isolated from illuminating gas in the early 19th century

hydroxybenzene

7

Cumene Furan Hydroquinone Indole Mesitylene

Phenol

phen + -ol; Gk phaino-, shining

3, 6

Pyridine

Gk pyro, fire

obtained by distillation of the oil derived from the pyrolysis of bones

pyridine

3

Pyrrole

Gk pyrro, fiery red

first detected by the red color produced when its vapor came in contact with pine splinters moistened with concentrated hydrochloric acid

pyrrole

3, 7

Resorcinol

resin + orcinol; It orcello, archil

orcinol (3,5-dihydroxytoluene); archil (or orchil) is a violet dye obtained from certain lichens; resorcinol forms when certain resins (from lichen?) are fused with potassium hydroxide

1,3-dihydroxybenzene

3, 7

Styrene

L styrax, storax

first obtained by distillation of liquid storax, a balsam from Liquidambar styraciflua and Liquidambar orientalis

ethenylbenzene

7

Toluene

obtained by distillation of tolu balsam, a fragrant, yellow-brown resin from the tolu tree, named after the seaport Santiago de Tolú, Colombia

methylbenzene

3, 5, 6

Xylene (o-, m-, p-) Gk xylon, wood

first obtained from wood tar

1,x-dimethylbenzene b

3

a Sp bx

indicates Spanish; Gk indicates Greek; L indicates Latin; G indicates German; It indicates Italian. The suffix -ol indicates an alcohol. = 2, 3, or 4.

Table 3. Carboxylic Acids Common Name a

Root b

Notes

Systematic Name

Ref 3, 8

Acetic acid

L acetum, vinegar

found in vinegar

ethanoic acid

Adipic acid

L adeps, fat

formed when some unsaturated fats are oxidized

hexanedioic acid

Butyric acid

L butyrum, butter

found in rancid butter

butanoic acid

3, 4, 8 3, 4, 8

7

Caproic acid

L caper, goat

found in goat’s milk and has a goatlike odor

hexanoic acid

Formic acid

L formica, ant

was obtained from the destructive distillation of ants

methanoic acid

3, 8

Fumaric acid

L fumus, smoke

found in the plant Fumaria, which was burned in ancient times to create smoke to ward off evil spirits

(E)-2-butenedioic acid

3, 8

first prepared from glutamic acid (an amino acid)

pentanedioic acid

7

L lac, milk

first isolated from sour milk

2-hydroxypropanoic acid

3

dodecanoic acid

5

the flax plant produces long silky fiber used to manufacture linen thread

(Z,Z)-9,12-octadecadienoic acid

6

Glutaric acid Lactic acid Lauric acid

L laurus, laurel

Linoleic acid

Gk linon, flax, + oleic

Maleic acid

L malum, apple

dehydration product of malic acid (which see)

(Z)-2-butenedioic acid

Malic acid

L malum, apple

first isolated from unripe apples

hydroxybutanedioic acid

3, 7 3, 7

Malonic acid

L malum, apple

first obtained by the oxidation of malic acid (which see)

propanedioic acid

Oleic acid

L oleum, oil

found in the triacylglycerols of some vegetable oils

(Z)-9-octadecenoic acid

Oxalic acid

Gk oxys, sharp, sour

has a sharp or sour taste; obtained from plants of the genus Oxalis

ethanedioic acid

Palmitic acid

L palma, palm

present in palm oil triacylglycerols

hexadecanoic acid

Propionic acid

Gk proto, first, and pion, fat

the smallest acid that shows characteristics of the larger fatty acids

propanoic acid

Pyruvic acid

Gk pyro, fire, and L uva, grape

obtained by the pyrolysis of tartaric acid (from grapes)

2-oxopropanoic acid

3

3 3, 9 3 3, 4 3

Stearic acid

Gk stear, tallow

present in the triacylglycerols of animal and vegetable fats

octadecanoic acid

Succinic acid

L succinum, amber

discovered in the distillate from the destructive distillation of amber

butanedioic acid

3, 8

from the root of the plant Valeriana officinalis, or garden heliotrope

pentanoic acid

3, 8

Valeric acid

3

a Although

systematic names are becoming more popular, the common names of these monocarboxylic and dicarboxylic acids are still frequently used in organic chemistry and biochemistry. b L indicates Latin; Gk indicates Greek.

JChemEd.chem.wisc.edu • Vol. 77 No. 1 January 2000 • Journal of Chemical Education

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